Abstract WP522: Catheter Ablation of Atrial Fibrillation and Long-Term Cardiovascular Outcomes

Abstract

Introduction: Catheter ablation is increasingly used in older patients with atrial fibrillation (AF) but the long-term effects on vascular outcomes in this population remain unclear. Methods: We used inpatient and outpatient claims between 2008-2015 from a nationally representative 5% sample of Medicare beneficiaries. Patients ≥66 years old who underwent AF ablation and control AF patients were matched in a 1:1 ratio based on a propensity score calculated from their age, sex, race, a socioeconomic status score, visit date, date of first AF diagnosis, history of vascular events, CHA 2 DS 2 -VASc score, and Charlson comorbidity index. Outcomes were ischemic stroke, myocardial infarction, heart failure hospitalization, major bleeding, number of AF hospitalizations, and all-cause mortality. Variables were ascertained using previously validated code algorithms. Survival statistics, Cox proportional hazards analysis, and Poisson regression were used to compare groups with adjustment for warfarin use during follow-up. Results: The 2,119 patients who underwent ablation and 2,119 controls were well matched, including on age (72.8 ±5.6 years), sex (39.5% female), race (92.5% white), CHA 2 DS 2 -VASc score (4.4 ±1.5), Charlson comorbidities (2.4 ±2.0), and duration since AF diagnosis (1.2 ±1.4 years). During 2.8 (±1.9) years of follow-up, ablation was associated with a lower risk of death (5.9% vs 10.8% per year) (HR, 0.55; 95% CI, 0.48-0.63) or heart failure hospitalization (5.9% vs 10.7% per year) (HR, 0.57; 95% CI, 0.47-0.70) and fewer AF hospitalizations (incidence rate ratio, 0.85; 95% CI, 0.81-0.89). There was no difference in the risk of ischemic stroke (0.9% vs 1.2% per year) (HR, 0.77; 95% CI, 0.54-1.12), myocardial infarction (0.8% vs 1.0% per year) (HR, 0.75; 95% CI, 0.50-1.11), or major bleeding (3.0% vs 3.4% per year) (HR, 0.90; 95% CI, 0.72-1.11). Conclusions: In a propensity-matched cohort of elderly AF patients, catheter AF ablation was associated with lower mortality and fewer hospitalizations for AF or heart failure, but ablation was not associated with a long-term reduction in thromboembolic or bleeding events.